The reason Steem never went anywhere was that nobody worked hard enough at promoting Steem.

100%

It would take over a decade for someone to self-vote themselves an equal amount of STEEM than they had to buy to self-vote.

but you are going on this from a point that he is losing his stake by self voting. because if he bought steem 6 months ago, self voted full for 6 months and sold yesterday he would have money invested + money from self voting. can't currently load his page to see who much he invested and how much he extracted from rewards.
His initial "investment" would be less worth only if shit like today happen, or everything crashes, or we all start to bot autovote ourselves. As long there is small % of people doing it, they profit and we are the fools for letting them do it. And yes i do agree that HF22 was a good thing to make it less effective. But again, all he has to do is set up bots and set autovote.

Ultimately Steem was designed to reward in SBD not STEEM in a healthy economy, and SBD rewards is greatly related to supply/demand of STEEM.

could be that self voting is even less effective in the healthy economy. I was getting almost nothing when SBD was really active, and we are in no SBD theritory for a long time, so i can admit i never did a real research of how all that would work.